My dog’s eyes seem to glow at night. Am I just imagining this? If not, why do they glow?
From the Editors of The Dog Daily
Dogs’ eyes do indeed glow at night. The effect is produced by a part of your dog’s eye called “tapetum.” This mirror-like structure is located at the back of your dog’s eye. It reflects light, so even the faintest amount of light shining on your dog in near-darkness will make your pet’s eyes glow.
The reflection allows your dog’s retina to register more light, permitting better vision in dimness. How much better? Your dog can see in light that is five times dimmer than you can see in, according to Dr. Paul Miller, a veterinary ophthalmologist and professor at the University of Wisconsin-Madison. Miller discovered this after extensively studying canine vision.
Your dog’s cool nighttime glow and good evening vision, however, come with a minor price, says Miller. Perfect human vision is described as 20:20. Dogs have 20:80 vision, he explains, since the tapetum scatters light, causing a slight degradation.